Dredging machine



May 30, 1939. J. SPADARO DREDG'ING MACHINE Filed Sept. 24, 1938 Patented May 30, 1939 I UNITED. mm

PATENT OFFiQE 2,160,761 DREDGING MACHINE Joseph Spadaro, Bronx, N. Y.

Application September 24, 1938, Serial No. 231,608

'7 Claims.

This invention relates to dredging mechanism broadly and is particularly concerned with dredges of that type utilizing a ladder carrying a cutter for displacing the material to be dredged. With dredges of this type, the conventional practice is to swing the dredge and ladder from side to side to bring the cutter into different positions as the machine advances during the dredging operation. Conventional practice in effecting this side to side or swinging movement of the ladder and dredge is to employ cables operated by a double drum hoist or the like, the cables usually extending for relatively great distances and being anchored at each end by means sufliciently rugged to stand the pull. Whenever the dredge moves forward a certain distance, say several hundred feet, the anchors are taken up and moved ahead so as to keep abreast of the dredge. This method is cumbersome and expensive, involves the use of a derrick barge and results in considerable delay, especially in shallow water where a derrick barge cannot be taken to move the anchors and cables.

The primary object of the present invention therefore is to provide means for initiating this side to side or swinging movement of the ladder and/or dredge which is relatively simple in construction as well as economical in operation, and which will eliminate the use'of partssuch as those involved in the commonly accepted prior or conventional methods. r

More specifically, the'invention contemplates a self-swinging dredge utilizing a propeller or propellers mounted in'a manner such as to exert a lateral propulsion movement on the ladder or hull of the dredge or on both, said propellers being rhounted below the water line and driven by means operable at the will of an operator.

The invention also contemplates the advantageous positioning and arrangement of selfswinging dredge propellers whereby themost efficient lateral propulsion action is obtained in a dredge of the type under consideration.

The foregoing and other objects and advantages will become apparent in view of theforegoing description taken in conjunction with the drawing, wherein;

Fig. l is a plan view'of a dredge embodying the features of the invention;

Fig. 2 is a view in side elevation of the machine; and

Fig. 3 is a fragmentary view of the forward end of the ladder, illustrating a modification in structure.

Referring to the drawing in detail, the numeral 5 generally designates the float, hull, platoon or analogous structure for supporting the dredging mechanism, the hull in this instance beingprovided with a bow 6 recessed to receive a dredging, ladder, generally indicated at I, said 5 ladder being pivotally mounted on bearings 8 connected in the recessed portion of the bow 6.

The hull is movably anchored during the dredging operation by the conventional spuds, indicated at 9 and 9a, which are shown mounted in supports Iii. As will be understood by those familiar with this art, the spuds are alternately raised when it is desired to advance the dredge, the anchored spud then serving as a pivot about which the machine swings or turns. 1 5

The ladder, as herein illustrated, is made up of structural members which define a skeleton framework for carrying a suction nozzle, cutter and other dredging mechanism. However, the

ladder. may be of any desired type, its specific construction forming no part of the present invention. The ladder has mounted therein a cutter shaft II, which at its upper or rear end is provided with drive mechanism l2 and at its front or dredging end carries a cutter I3. A suc- 25 tion tube 14 is also carried by the latter and extends forward to the dredging end thereof to effect removal of the material as it is displaced by the cutter.

The present invention is primarily concerned 30 with a novel means of effecting a swinging action of the dredge and the ladder carried thereby in order to bring the cutter it into different positions of cut or displacement during the dredging operation, said means consisting of one or more .35 propellers positioned in a manner such as to exert a lateral propulsion action on the dredge and/or ladder. In Fig. 1, a series of propellers are used, both on the ladder of the dredge, said propellers being indicated at l5, l6, H and I8. 1'40 The ladder propellers l5 and it, as illustrated, are driven through the medium of a motor or engine [3 which connects with the propellers I5 and Hi through the medium of a drive shaft 20 mounted in bearings 2|, the connection with the propellers being through transmission mechanism or'gearing generally indicated at 22.

In some instances it may be desirable to drive the propellers l5 and IE directly from the cutter drive shaft H, as illustrated in Fig. 3, the cutter 50 drive shaft in this latter figure being indicated at Ila and the cutter at lta. The shaft l la may be provided with a worm drive gear 23 which may be connected to the transmission mechanism 22a. In this manner, the use of a motor 55 I9 and shaft 20 may be obviated, although in certain instances a separate drive has its advantages. Instead of connecting the worm 23 with transmission gearing 22a, the connection may be direct.

The propellers I! and I8, as illustrated, are provided with separate motors 24 and 25.

In operation, the respective propellers l5, I6, I! and I8, (assuming all are to be used), may be driven continuously, or intermittently, depending upon the type of material being excavated or dredged. Assuming that the propellers l and I! act independently of the propellers l6 and I8, then if the movement is to be in an arcuate direction toward the right as viewed in Fig. 1, these propellers would be driven at a rate of speed such as would bring about the desired propulsion action and resultant movement or drift of the cutter I? as the material is displaced. The spud 9 would remain in anchored position while the spud to would be raised clear of the bottom of the channel, permitting the machine to pivot about the spud 9. If the drift is in the reverse direction, or toward the left as viewed in Fig, 1, then the propellers l6 and 3 would be brought into play, the spud 9 raised and the machine caused to pivot about the spud 9a.

If the propellers l5, l6, l1 and I8 all work in harmony, or have the blades thereof canted in the same direction, then the entire series of propellers can be used at one time, and to obtain a reverse movement or drift of the cutter, the drive can be reversed through the use of reversible motors o-r suitable reverse gear shift mechanism.

The type of drive used is immaterial. In the present instance, the prime mover in each instance is illustrated as an electric motor, in which case a suitable generating plant would be carried by the dredge. Obviously, however, steam or Diesel power may be used, or any type of power convenient for the particular installation.

Obviously, certain variations in structure are contemplated within the scope of the invention,

as defined by the appended claims. For example, a single propeller may be used instead of a series of propellers, the propeller being mounted at a point below the water line and arranged to impose a lateral propulsion action on the dredge and ladder. Also, the two propellers mounted on the ladder may be sufficient, or the two on the bow of the hull, or one reversible propeller on the ladder and one on the hull.

I claim:

1. In a dredging machine, a float, hull or the like, a ladder movably connected at one extremity to said float and at its opposite extremity being submerged below the water line during dredging, a propeller mounted on a submerged portion of said ladder and adapted, when driven, to exert lateral propulsion on the ladder to thereby swing the ladder from side to side during the dredging operation, and means for driving the propeller.

2. In a dredging machine, a float, hullor the like for supporting dredging mechanism, a ladder movably connected at one extremity to said float and at its opposite extremity being submerged when dredging, a propeller mounted on the ladder along a submerged portion of the latter and arranged to exert a lateral propulsion action on the ladder, and selective means for driving the propeller to effect lateral motion of the ladder during the dredging operation.

3. In a dredging machine, a float, hull or the like supporting dredging mechanism, a ladder movably connected at one extremity to said float and at its opposite extremity being submerged during the dredging operation, a rotatable cutter at the submerged end of the ladder for efiectin displacement of the material to be dredged, means for driving said cutter, and a propeller operatively connected to said driving means and arranged to exert a lateral propulsion action on the ladder and swing the same from side to side during the dredging operation.

4. In a dredging machine, a float, hull or the like supporting dredging mechanism, a ladder movably connected at one extremity to said float and at its opposite extremity being submerged during the dredging operation, a propeller mounted on'the ladder along a submerged portion of the latter and arranged, when driven, to exert a lateral propulsion action on the ladder, an auxiliary or additional propelling means mounted on the bow of the float below the water line and arranged to assist or augment said first named propellers, and means for selectively driving said propellers.

5. In a dredging machine, a float, hull or the like supporting dredging mechanism, a ladder pivotally connected at one extremity to said float and at its opposite extremity being submerged during the dredging operation, a propeller mounted on the ladder along a submerged portion of the latter and arranged to exert, when driven, a lateral propulsion action on the ladder, means mounted on the machine above the water line for driving said propeller, and power transmission mechanism operatively connecting said driving means with said propeller.

6. In a dredging machine, a float, hull or the like supporting dredging mechanism, a ladder pivotally connected at one extremity to said float, means mounted on the opposite extremity of the ladder for effecting displacement of the material to be dredged, and coacting propellers mounted on opposite sides of the ladder along a submerged portion thereof and arranged, when driven, to effect lateral movement of the ladder during the dredging operation.

7. In a dredging machine, a float, hull or the like supporting dredging mechanism, a ladder movably connected at one extremity to said float and at its opposite extremity being submerged during the dredging operation, means carried by the submerged end of the ladder for effecting displacement of the material to be dredged, means for actuating said displacing means, a, propeller mounted on said ladder along the submerged portion of the same and disposed to exert, when driven, a. lateral propulsion action on the ladder to swing the samefrom side to side during the dredging operation, a motor for driving the propeller mounted on said ladder above the submerged portion of the same, and driving means 

